Preheat the oven to 350 degrees.
Thoroughly butter the inside of a sauté pan, including the sides.
Take the leftover roasted vegetables and spread them evenly on the bottom of the sauté pan.
Crack the eggs into a large bowl and whisk to break up the yolks.
Add the sour cream, salt and pepper. Whisk together thoroughly. Add one cup shredded cheese, mix again. Pour over the vegetables.
Place in the preheated oven for 25-30 minutes until the frittata is puffed and golden brown and it is set in the middle.
Remove from the oven, top with the remaining shredded cheese. Place back into the oven for another three minutes or until the cheese is melted and golden brown.
Slice, add toppings of choice, serve and enjoy!